Soak lily buds and fungus in warm water to cover for 30 minutes; drain.
Pinch off and discard hard tips of lily buds; cut buds in half lengthwise.
Pinch out and discard hard, knobby centers of fungus; thinly slice remaining fungus.
Set aside.
In a bowl, combine cornstarch, soy, and sherry.
Add pork and stir to coat.
Stir in 1 1/2 teaspoons of the oil.
Let marinate for 15 minutes.
Cut onions into 1 1/2-inch lengths; then cut lengthwise into shreds.
Reserve half the onion shreds for cooking; set other half aside to offer at the table.
In a bowl, lightly beat eggs with salt.
Heat a wok or 10- to 12-inch frying pan over medium-high heat.
When pan is hot, add 1 tablespoon of the oil.
When oil is hot, add eggs and cook, stirring, until softly set; then slide out of pan.
Pour remaining 2 tablespoons oil into pan and increase heat to high.
When oil is hot, add ginger and stir once.
Add pork mixture and stir until lightly browned, about 4 minutes.
Add lily buds and fungus and stir for 1 minute, adding a few drops of water if pan appears dry.
Add bamboo shoots, carrot, lettuce, reserved onion shreds, and Cooking Sauce; cook, stirring, just until lettuce is wilted, about 2 minutes.
Stir in eggs, breaking them into bite-size pieces.
When eggs are hot, pour mixture into a serving dish and serve at once.
Have on the table Mandarin Pancakes, hoisin, onion shreds, and onion brushes.
To eat, paint a little hoisin on a pancake with an onion brush, spoon on some of the meat mixture, and garnish with onion shreds.
Wrap to enclose filling; eat out of hand.